Centers for Disease Control and Prevention Global Health Odyssey Museum Tom Harkin Global Communications Center July 6-10, 2009 Teach Epidemiology Professional Development Workshop Day 4

2 Teach Epidemiology

3 Enduring Epidemiological Understandings Ken Bain, What the Best College Teachers Do “… they can distinguish between foundational concepts and elaborations or illustrations of those ideas.”

4 Teach Epidemiology Enduring Epidemiological Understandings Ken Bain, What the Best College Teachers Do “… they can distinguish between foundational concepts and elaborations or illustrations of those ideas.”

5 Teach Epidemiology John Snow, MD ( ) Father of Epidemiology “On the Mode and Transmission of Cholera” Making Group Comparisons and Identifying Associations

6 Teach Epidemiology Making Group Comparisons and Identifying Associations

7 Teach Epidemiology Making Group Comparisons and Identifying Associations

8 Teach Epidemiology Making Group Comparisons and Identifying Associations

9 Teach Epidemiology Making Group Comparisons and Identifying Associations

10 Teach Epidemiology Making Group Comparisons and Identifying Associations

11 Teach Epidemiology Making Group Comparisons and Identifying Associations

12 Teach Epidemiology Golden Square, London Making Group Comparisons and Identifying Associations

Teach Epidemiology (Tuesday) CDC June

14

15

16 Teach Epidemiology Making Group Comparisons and Identifying Associations

17... the intermixing of the water supply of the Southwark and Vauxhall Company with that of the Lambeth Company, over an extensive part of London, admitted of the subject being sifted in such a way as to yield the most incontrovertible proof on one side or the other. In the sub-districts enumerated in the above table as being supplied by both Companies, the mixing of the supply is of the most intimate kind. The pipes of each Company go down all the streets, and into nearly all the courts and alleys. A few houses are supplied by one Company and a few by the other, according to the decision of the owner or the occupier at the time when the Water Companies were in active competition. In many cases a single house has a supply different from that on either side. Each company supplies both rich and poor, both large houses and small; there is no difference either in the condition or occupation of the persons receiving the water of the different Companies. Now it must be evident that, if the diminution of cholera, in the districts partly supplied with the improved water, depended on this supply, the houses receiving it would be the houses enjoying the whole benefit of the diminution of the malady, whilst the houses supplied with the water from Battersea Fields would suffer the same mortality as they would if the improved supply did not exist at all. As there is no difference whatever, either in the houses of the people receiving the supply of the two Water Companies, or in any of the physical conditions with which they are surrounded, it is obvious that no experiment could have been devised which would more thoroughly test the effect of water supply on the progress of cholera than this, which circumstances placed ready made before the observer. The experiment, too, was on the grandest scale. No fewer than three hundred thousand people of both sexes, of every age and occupation, and of every rank and station, from gentlefolks down to the very poor, were divided in to two groups, without their choice, and, in most cases, without their knowledge; one group being supplied with water containing the sewage of London, and, amongst it, whatever might have come from the cholera patients, the other group having water quite free from such impurity. To turn this grand experiment to account, all that was required was to learn the supply of water to each individual house where a fatal attack of cholera might occur.

18

Epidemiologists make rates, compare rates, and makes inferences based on their similarities or differences.

Epidemiologists make rates, compare rates, and makes inferences based on their similarities or differences.

21

22 Time Check 9:15 AM

23

24 Teach Epidemiology

25 Epidemiology... the study of the distribution and determinants of health- related states or events in specified populations and the application of this study to the control of health problems. Leon Gordis, Epidemiology, 3 rd Edition, Elsevier Saunders, 2004.

26 Outcome If an association was causal, …. Hypothesized Exposure X X … and you avoided or eliminated the hypothesized cause, what would happen to the outcome? causal, …. ? Control of Health Problems

27 Outcome If the association was found due to confounding, …. Hypothesized Exposure Unobserved Exposure X … and you avoided or eliminated the hypothesized cause, what would happen to the outcome? ? found due to confounding, …. Control of Health Problems

28 Hypothesized Exposure Outcome If an association was found due to reversed time-order, …. found due to reversed time order, …. X … and you avoided or eliminated the hypothesized cause, what would happen to the outcome? ? Control of Health Problems

29 Outcome If an association was found due to chance, …. Hypothesized Exposure found due to chance, …. X … and you avoided or eliminated the hypothesized cause, what would happen to the outcome? ? Control of Health Problems

30 Outcome If an association was found due to bias, …. Hypothesized Exposure ? found due to bias, …. X … and you avoided or eliminated the hypothesized cause, what would happen to the outcome? Control of Health Problems

31 Outcome If an association was causal, …. Hypothesized Exposure X X … and you avoided or eliminated the hypothesized cause, what would happen to the outcome? causal, ….... the study of the distribution and determinants of health-related states or events in specified populations and the application of this study to the control of health problems. Control of Health Problems

32 1.Cause 2.Confounding 3.Reverse Time Order 4. Chance 5.Bias... the study of the distribution and determinants of health-related states or events in specified populations and the application of this study to the control of health problems. Control of Health Problems

33 Suicide Higher in Areas with Guns Family Meals Are Good for Mental Health Lack of High School Diploma Tied to US Death Rate Study Links Spanking to Aggression Study Concludes: Movies Influence Youth Smoking Study Links Iron Deficiency to Math Scores Kids Who Watch R-Rated Movies More Likely to Drink, Smoke Pollution Linked with Birth Defects in US Study 1.Cause 2.Confounding 3.Reverse Time Order 4. Chance 5.Bias Snacks Key to Kids’ TV- Linked Obesity: China Study Depressed Teens More Likely to Smoke Ties, Links, Relationships, and Associations

34 Teach Epidemiology Enduring Epidemiological Understandings

35

36 Suicide Higher in Areas with Guns Family Meals Are Good for Mental Health Lack of High School Diploma Tied to US Death Rate Study Links Spanking to Aggression Study Concludes: Movies Influence Youth Smoking Study Links Iron Deficiency to Math Scores Kids Who Watch R-Rated Movies More Likely to Drink, Smoke Pollution Linked with Birth Defects in US Study Ties, Links, Relationships, and Associations Snacks Key to Kids’ TV- Linked Obesity: China Study Depressed Teens More Likely to Smoke

37 Suicide Higher in Areas with Guns Family Meals Are Good for Mental Health Lack of High School Diploma Tied to US Death Rate Study Links Spanking to Aggression Study Concludes: Movies Influence Youth Smoking Study Links Iron Deficiency to Math Scores Kids Who Watch R-Rated Movies More Likely to Drink, Smoke Pollution Linked with Birth Defects in US Study Snacks Key to Kids’ TV- Linked Obesity: China Study Depressed Teens More Likely to Smoke Ties, Links, Relationships, and Associations

38 1.Cause 2.Confounding 3.Reverse Time Order 4. Chance 5.Bias Possible Explanations for Finding an Association

39 Epidemiology... the study of the distribution and determinants of health- related states or events in specified populations and the application of this study to the control of health problems. Leon Gordis, Epidemiology, 3 rd Edition, Elsevier Saunders, 2004.

40 1.Cause 2.Confounding 3.Reverse Time Order 4. Chance 5.Bias Possible Explanations for Finding an Association

41 Cause A factor that produces a change in another factor. William A. Oleckno, Essential Epidemiology: Principles and Applications, Waveland Press, Possible Explanations for Finding an Association

42 Sample of 100

43 Sample of 100, 25 are Sick

44 Diagram 2x2 Table DZ X X ab c d Types of Causal Relationships

45 DZ X X ab c d Diagram 2x2 Table Types of Causal Relationships

46 Handout

47 X X X X X X X X X X X X X X XX X X X X X X X X X XDZ X X ab c d X Diagram 2x2 Table Necessary and Sufficient

48 DZ X X ab c d X XX++ X X X X X X X X X X X X X X X XX X X X X X X X X X X X X X X X X X XX Diagram 2x2 Table Necessary but Not Sufficient

49 X X X X X X X X X X X X X X X X DZ X X ab c d X X X X Diagram 2x2 Table Not Necessary but Sufficient

50 DZ X X ab c d X X X X X X X X X X X X X X X X X X X X X X X X X X X X X XX X X X XX++ XX++ XX++ Not Necessary and Not Sufficient Diagram 2x2 Table

51 a b c d Heart Attack No Heart Attack Lack of Fitness No Lack of Fitness Lack of fitness and physical activity causes heart attacks.

52 a b c d Lead Poisoning No Lead Poisoning Lack of Supervision No Lack of Supervision Lack of supervision of small children causes lead poisoning.

53 Is the association causal?

54 Suicide Higher in Areas with Guns Family Meals Are Good for Mental Health Lack of High School Diploma Tied to US Death Rate Study Links Spanking to Aggression Study Concludes: Movies Influence Youth Smoking Study Links Iron Deficiency to Math Scores Kids Who Watch R-Rated Movies More Likely to Drink, Smoke Pollution Linked with Birth Defects in US Study Ties, Links, Relationships, and Associations 1.Cause 2.Confounding 3.Reverse Time Order 4. Chance 5.Bias Snacks Key to Kids’ TV- Linked Obesity: China Study Depressed Teens More Likely to Smoke

55

56 1.Cause 2.Confounding 3.Reverse Time Order 4. Chance 5.Bias Possible Explanations for Finding an Association

57 All the people in a particular group. Population Possible Explanations for Finding an Association

58 A selection of people from a population. Sample Possible Explanations for Finding an Association

59 Inference Process of predicting from what is observed in a sample to what is not observed in a population. To generalize back to the source population. Possible Explanations for Finding an Association

60 Sample Population Process of predicting from what is observed to what is not observed. Observed Not Observed Inference

61 Deck of 100 cards Population

62 a 25 cards b c d Population

63 = Population a 25 cards bc d = ab cd Odd # Even # No Marijuana Population Total

64 = Population a 25 cards bc d = Total Odd # Even # No Marijuana Population

65 = Population = M&M’s No M&M’s Flu No Flu Total = Total a 25 cards bc d Odd # Even # No Marijuana Population

66 = Population = Total a 25 cards bc d Risk 25 / 50 or 50% Odd # Even # No Marijuana Population

67 = Population a 25 cards bc d = TotalRiskRelative Risk 25 / 50 or 50 % 50 % / 50% = = 1 50 % ____ Odd # Even # No Marijuana Population

68 25 cards Population

69 To occur accidentally. To occur without design. Chance A coincidence. Possible Explanations for Finding an Association

70 Chance

71 Chance

72 Population Sample b Sample of 20 cards 25 cards Sample

73 Population Sample b Sample of 20 cards 25 cards 10 Total Odd # Even # No Marijuana Sample

74 Population Sample b Sample of 20 cards 25 cards 10 Total Risk 5 / 10 or 50 % Odd # Even # No Marijuana Sample

75 Population Sample b Sample of 20 cards 25 cards 10 Total Risk 5 / 10 or 50 % Odd # Even # No Marijuana Sample Relative Risk 50 % / 50% = = 1 50 % ____

76 b Sample of 20 cards Total Risk 5 / 10 = 50 % 50 1 Relative Risk By Chance CDC % ___ % = Odd # Even # No Marijuana Sample

77 10 Total Risk 5 / 10 or 50 % Relative Risk How many students picked a sample with 5 people in each cell? = 1 50 % ____ Odd # Even # No Marijuana Chance By Chance

78 Relative Risks Greater than 1Less than 1 Chance

79 Study Links Having an Odd Address to Marijuana Use Ties, Links, Relationships, and Associations

80 Relative Risks Greater than 1Less than 1 Possible Explanations for Finding an Association

81 Study Links Having an Even Address to Marijuana Use Ties, Links, Relationships, and Associations

82 Relative Risks Greater than 1Less than 1 1 By Chance 25 cards Chance

83 b Sample of 20 cards Total Risk 5 / 10 = 50 % 50 Relative Risk 50 % ___ % = Odd # Even # No Marijuana Different Sample Sizes

84 Relative Risks Greater than 1Less than 1 1 By Chance 25 cards Chance 50 cards

85 b Sample of 20 cards Total Risk 5 / 10 = 50 % 50 Relative Risk 75 % ___ % = Odd # Even # No Marijuana Different Sample Sizes

86 Relative Risks Greater than 1Less than 1 1 By Chance 25 cards Chance 75 cards

87 b Sample of 20 cards Total Risk 5 / 10 = 50 % 50 1 Relative Risk 99 % ___ % = Odd # Even # No Marijuana Different Sample Sizes

88 Relative Risks Greater than 1Less than 1 1 By Chance 25 cards Chance 99 cards

89 Suicide Higher in Areas with Guns Family Meals Are Good for Mental Health Lack of High School Diploma Tied to US Death Rate Study Links Spanking to Aggression Study Concludes: Movies Influence Youth Smoking Study Links Iron Deficiency to Math Scores Kids Who Watch R-Rated Movies More Likely to Drink, Smoke 1.Cause 2.Confounding 3.Reverse Time Order 4. Chance 5.Bias Snacks Key to Kids’ TV- Linked Obesity: China Study Depressed Teens More Likely to Smoke Association is not necessarily causation. Ties, Links, Relationships, and Associations

90

Teach Epidemiology Explaining Associations and Judging Causation

1.Cause 2.Confounding 3.Reverse Time Order 4. Chance 5.Bias Teach Epidemiology Explaining Associations and Judging Causation Coffee and Cancer of the Pancreas

93

94 Guilt or Innocence?Causal or Not Causal? Does evidence from an aggregate of studies support a cause-effect relationship? Teach Epidemiology Explaining Associations and Judging Causation

95 Sir Austin Bradford Hill “The Environment and Disease: Association or Causation?” Proceedings of the Royal Society of Medicine January 14, 1965 Teach Epidemiology Explaining Associations and Judging Causation Handout

96 “In what circumstances can we pass from this observed association to a verdict of causation?” Teach Epidemiology Explaining Associations and Judging Causation

97 “Here then are nine different viewpoints from all of which we should study association before we cry causation.” Teach Epidemiology Explaining Associations and Judging Causation

Does evidence from an aggregate of studies support a cause-effect relationship? 1. What is the strength of the association between the risk factor and the disease? 2. Can a biological gradient be demonstrated? 3. Is the finding consistent? Has it been replicated by others in other places? 4. Have studies established that the risk factor precedes the disease? 5. Is the risk factor associated with one disease or many different diseases? 6. Is the new finding coherent with earlier knowledge about the risk factor and the m disease? 7. Are the implications of the observed findings biologically sensible? 8. Is there experimental evidence, in humans or animals, in which the disease has m been produced by controlled administration of the risk factor? Teach Epidemiology Explaining Associations and Judging Causation

Handout Teach Epidemiology Explaining Associations and Judging Causation

Timeline Cohort Study Randomized Controlled Trial Timeline Case-Control Study Timeline Cross-Sectional Study Timeline E E O O O O E E E E Healthy People E Random Assignment E O O O O Healthy People E E O O O O Teach Epidemiology Explaining Associations and Judging Causation

Teach Epidemiology Explaining Associations and Judging Causation Handout

102 Stress causes ulcers. Helicobacter pylori causes ulcers. Teach Epidemiology Explaining Associations and Judging Causation

103 * * * * * * * * * Teach Epidemiology Explaining Associations and Judging Causation

104 Teach Epidemiology Explaining Associations and Judging Causation

105

106 “Does Playing Video Games Cause Asthma?” Teach Epidemiology Explaining Associations and Judging Causation Handout

107 Time Check 11:45 AM

108

109 Teach Epidemiology

110 Time Check 12:15 PM

111

112 Teach Epidemiology

113 Teach Epidemiology

114 Rules 1.Teach epidemiology 2.As a group, create a 20-minute lesson during which we will develop a deeper understanding of an enduring epidemiological understanding. 3.Focus on the portion of the unit that is assigned. Use that portion of the unit as the starting point for creating your 20-minute lesson. 4.When teaching assume the foundational epidemiological knowledge from the preceding days of the workshop. 5.Try to get us to uncover the enduring epidemiological understanding. Try to only tell us something when absolutely necessary. 6.End each lesson by placing it in the context of the appropriate enduring epidemiological understanding. 7.Be certain that the lesson is taught in 20 minutes or less. 8.Teach epidemiology. Teach Epidemiology Teaching Epidemiology

115 They can then use that ability to think about their own thinking … to grasp how other people might learn. They know what has to come first, and they can distinguish between foundational concepts and elaborations or illustrations of those ideas. They realize where people are likely to face difficulties developing their own comprehension, and they can use that understanding to simplify and clarify complex topics for others, tell the right story, or raise a powerfully provocative question. Ken Bain, What the Best College Teachers Do Teach Epidemiology Teaching Epidemiology Metacognition

116 To create “… a professional community that discusses new teacher materials and strategies and that supports the risk taking and struggle entailed in transforming practice.” Teach Epidemiology Teaching Epidemiology

Class 1 Pages Teach Epidemiology Teaching Epidemiology Group 1

118 Teach Epidemiology Teaching Epidemiology Group 2 Pages 35-39

119 Teach Epidemiology Teaching Epidemiology Group 3 Class 1 Pages 16-21)

120 Teach Epidemiology Teaching Epidemiology Group 4 Pages 32-36

121 Teach Epidemiology Teaching Epidemiology Group 5 Pages and 30-32

122 Teach Epidemiology Teaching Epidemiology Group 6 Procedures 2, 4, and 5

123

124 Time Check 1:45 PM

125

126 Teach Epidemiology

127 Teach Epidemiology Teaching Epidemiology Group 1

128 They can then use that ability to think about their own thinking … to grasp how other people might learn. They know what has to come first, and they can distinguish between foundational concepts and elaborations or illustrations of those ideas. They realize where people are likely to face difficulties developing their own comprehension, and they can use that understanding to simplify and clarify complex topics for others, tell the right story, or raise a powerfully provocative question. Ken Bain, What the Best College Teachers Do Teach Epidemiology Teaching Epidemiology Metacognition

129 National Research Council, Learning and Understanding Teach Epidemiology Enduring Epidemiological Understandings Knowledge that “… is connected and organized, and … ‘conditionalized’ to specify the context in which it is applicable.”

130 Time Check 2:30 PM

131

132 Teach Epidemiology

133 Teach Epidemiology Teaching Epidemiology Group 3

134 They can then use that ability to think about their own thinking … to grasp how other people might learn. They know what has to come first, and they can distinguish between foundational concepts and elaborations or illustrations of those ideas. They realize where people are likely to face difficulties developing their own comprehension, and they can use that understanding to simplify and clarify complex topics for others, tell the right story, or raise a powerfully provocative question. Ken Bain, What the Best College Teachers Do Teach Epidemiology Teaching Epidemiology Metacognition

135 National Research Council, Learning and Understanding Teach Epidemiology Enduring Epidemiological Understandings Knowledge that “… is connected and organized, and … ‘conditionalized’ to specify the context in which it is applicable.”

136 Time Check 3:15 PM

137

138 Teach Epidemiology

139 Teach Epidemiology Teaching Epidemiology Group 2

140 They can then use that ability to think about their own thinking … to grasp how other people might learn. They know what has to come first, and they can distinguish between foundational concepts and elaborations or illustrations of those ideas. They realize where people are likely to face difficulties developing their own comprehension, and they can use that understanding to simplify and clarify complex topics for others, tell the right story, or raise a powerfully provocative question. Ken Bain, What the Best College Teachers Do Teach Epidemiology Teaching Epidemiology Metacognition

141 National Research Council, Learning and Understanding Teach Epidemiology Enduring Epidemiological Understandings Knowledge that “… is connected and organized, and … ‘conditionalized’ to specify the context in which it is applicable.”

142 Time Check 4:00 PM